Compared to other free weights, kettlebells seem disproportionately expensive per kg. A quick search turns up only speculation, so an acceptable answer should have a source.
Plausible(?) hypothesis from the internet:
- Shipping is expensive
- Production happens only overseas (corroborates with 1.)
- Low demand -> low supply and higher prices
- Different material (are they any different internally than other weights?)
- Higher production costs due to shape
Why are kettlebells so expensive?